Pedestrian traffic is regulated by
§25 and
§26 StVO, and mostly codifies what one would consider common sense. Cross the bloody road in a straight line, don't bumble about, don't run head-first into full traffic. Pedestrians crossing a red light may be fined 5€, or 10€ if their malovelent street-crossing rampage causes any damage to property. I'm not even kidding. See
BKatV, Lfd. Nr. 130ff. Of course that's in German only, sorry.
To sum things up: There is no regulation explicitly prohibiting jaywalking, but there is a 5€ fine for crossing a red light as a pedestrian. There is no "acceptable distance of a traffic light" known to me which would require you by law to use it instead of just crossing the road. You may never cross a road if you have to step over/under any chains or other objects blocking access to the road. Those are there for a reason.
On the way from the train station/overflow hotel, there's a large-ish road to cross (the Otto-von-Guericke-Str.), with traffic lights being only a few dozen meters off. It is rather common to cross this road "jaywalking style", and relatively safe to do so. All the cool kids are doing it.
An overzealous cop MAY approach you for a lecture, though, if he considers the traffic lights down the road to be "close enough", though. If you want to take this to court, feel free, otherwise just stick to walking the ~30m extra to the nearest crossing, and feel good about yourself doing the right thing.